Species · GBIF taxon 5190072
Blue Dragon
Glaucus atlanticusAlso known as Blue Sea Slug, Blue Angel, Sea Swallow, Blue Glaucus
Blue dragons are pelagic nudibranchs that spend their lives floating upside down on the surface tension of the open ocean. They use their dark blue underbellies to blend with the water from above, while their silvery backs camouflage them from predators looking up from below. By feeding on venomous siphonophores, they concentrate stinging cells in their finger-like cerata to use as a potent defense.
PelagicVenomousCamouflaged
Licensed reference(c) Sylke Rohrlach, some rights reserved (CC BY-SA) · cc-by-sa
- diet
- Venomous siphonophores, including Portuguese man o' war, blue buttons, and by-the-wind sailors
- family
- Glaucidae
- threats
- Ocean acidification, warming sea temperatures, and marine pollution
- life Span
- Up to 1 year
NE
Concentrates potent stinging cells from its prey; do not touch even when washed up on beaches.
Stores concentrated, highly potent nematocysts harvested from the Portuguese man o' war in its cerata, delivering an incredibly painful sting.
Never touch or pick up a blue dragon, even if it appears dead on the sand; use a stick or bucket if it must be moved.- Look for drift lines: Search along sandy beaches after strong onshore winds, which push these surface-drifters ashore.
- Never touch: Avoid handling live or dead specimens, as their concentrated sting can be extremely painful.
- Observe the orientation: Notice how they float upside down, using surface tension to stay suspended.